Expensive metal such as gold, white gold or silver is utilized as the raw material of various decorative and practical products. In fact, some credit cards and decorative articles are made in golden color in order to emphasize their noble value. Thus, it is valuable to develop the technique of manufacturing actual gold cards with relative low cost for those noble cards, such as golden credit card, VIP membership card, birthday card, and festival card, etc.
However, due to the soft nature of pure gold, the pure gold or silver cards and decorative articles are not durable. In addition, in order to reduce the cost as much as possible, the preferred thickness of the valuable metal foil is from 0.01 mm to 1 mm which is similar to or even thinner than the thickness of a piece of paper. But, the thin metal foils made of gold, white gold or silver unlike the rigid papers may easily be folded with wrinkles and rolled up to form a coil.
U.S. Pat. No. 5,702,554 that was issued to the inventor of the present invention on Dec. 31, 1997, successfully solves the above problems by providing a process of laminating gold foil which enables a soft and very thin gold with thickness less than 1 mm to be laminated with transparent plastic sheets on both sides to form gold foil card without air bubbles formed therebetween and scrapes formed on the gold foil surfaces.
Although the U.S. Pat. No. 5,702,554 provides a durable gold foil card that is specifically excellent to be used as the raw material for producing credit cards or VIP cards, when the gold foil card is used as the raw material of decorative articles, it still has a drawback that the excellent tactile impression of gold is sheltered by the plastic layers integrally attached on both sides of the gold foil. It will substantially degrade the decoration or display value. However, it seems impossible to merely laminate one side of the thin metal foil by the prior lamination process.